How to scroll WebView to top in android?

In Android, if you want to scroll a WebView to the top programmatically, you can use the following method:

java
webView.scrollTo(0, 0);

Alternatively, if you want a smooth scrolling effect, you can use the smoothScrollTo method:

java
webView.smoothScrollTo(0, 0);

Here's a concrete example: Suppose your Android application has a WebView used to display content, and in certain cases, such as when a user clicks a 'Scroll to Top' button, you want the WebView to scroll to the top. You can add the following code in the button's click event listener:

java
Button scrollToTopButton = findViewById(R.id.scroll_to_top_button);
scrollToTopButton.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        // If you want to scroll to the top immediately:
        webView.scrollTo(0, 0);

        // If you want to scroll to the top smoothly:
        // webView.smoothScrollTo(0, 0);
    }
});

In this example, we first locate the button using findViewById and set up a click event listener for it. When the user clicks scrollToTopButton, the WebView will scroll back to the top immediately or smoothly, depending on whether you use scrollTo or smoothScrollTo.

Ensure that these operations are performed on the main thread in your actual application, as UI operations must be executed on the main thread. If you call these methods from a background thread, you need to use the runOnUiThread method or a Handler to ensure these operations are executed on the main thread.